3. Branchiostoma belcheri.
Ampliioxus belcheri, Gray, P. Z. S. 1847, p. 35.
Branchiostoma belcheri, Gray, Chondropt. p. 150.
Myocommas 37 + 14 + 1 3 = 6 4 (Borneo).
37 + 14 + 14 = 65 (Prince of AVales Isl.).
This Lancelet is very similar to, but rather more elongate than,
B. lanceolatum, and the fins, instead of being dilated behind, gradually
decrease in width towards the extremity of the tail.
The specimens were collected partly by Sir E. Belcher during the
cruise of H.M.S. ‘ Samarang’ on the coast of Borneo, partly by
Hr. Coppinger at Prince of Wales Island, Torres Straits.
4. Branchiostoma caribæum.
Sundevall, I. c. 1853, p. 12.
Myocommas 37 + 1 4 + 9 = 60 (Sundevall).
37 + 14 + 9 = 60.
37 + 1 3 + 9 = 59.
Distinguished from B . belcheri and lanceolatum by the shortness
of its tail and by the attenuated form of the extremities of the body.
St. Thomas ; Bio de Janeiro ; mouth of the Plate river.
I am indebted for specimens of this species to the kindness of
Prof. Ed. A^au Beneden, who obtained them in great numbers
in the Bay of Botafogo ; they are the same species on which Moreau
made his researches on the structure of the notochord (Bull. Ac.
Hoy. Belg. 1875, p. 312). The name of Amphioxus mUlleri (Kroyer,
MS.) was adopted for them ; but, as this has never been described,
it is doubtful whether the name was intended for this or some
other species.
5. Branchiostoma lanceolatum (Pall.).
Myocommas 35 + 1 2 + 1 2 = 5 9 (Polperro).
36 + 14 + 11 = 61 (Scandin., Sundevall').
34 + 13 + 1 3 = 6 0 (Naples).
35 + 12 + 1 3 = 6 0 (Naples)*.
Coasts of Europe ; Atlantic coasts of North America.
6. Branchiostoma cultellum.
Epigonichthys cultellus, Peters, Berl. MB. 1876, p. 327 (c. fig.).
Myocommas 32 + 10 + 10 = 52, or
31 + 11 + 1 0 = 5 2 .
Anterior part of the dorsal fin high ; fin between branchial porus
♦ I take this opportunity of correcting an error on p. 63 of ‘ Study of
Fishes,’ where in fig. 28 the letters b and c hare inadvertently been reversed.
and extremity of tail very rudimentary or partly absent. Vent in,
or nearly in, tho median line.
Moreton Bay (Peters) ; Thursday Island (Dr. Coppinger).
In our specimens the fin occupying the median line between the
branchial or abdominal pore and the caudal extremity is rather
more distinct than would seem to have been the case in the specimens
described and figured by Peters ; aud consequently the position of
the vent is, at least in some of our specimens, rather lateral than
median. AATiether those differences are owing to the better state of
preservation of our specimens, or related to the difference of locality,
I am not prepared to decide ; but assuming the latter to be the case,
I should not consider them sufficient for specific distinction. Further,
as our specimens show distinct traces of a postanal fin and a sublateral
position of the vent, they clearly indicate th a t Epigonichthys
cannot be maintained as a distinct genus.
Í'!
r